Surf boards

ABSTRACT

A surf board having a hull with sufficient buoyancy to support a rider is provided with a seat which is pivotally mounted so that it can turn about an upright axis and a rudder which is connected to the seat so that the rider can steer the surf board by twisting the seat. A catch for the attachment of a towrope to the hull is provided on the underside of the bow of the hull and the catch has a release mechanism controlled by a member which extends towards the seat to enable it to be held by the rider. The release mechanism is so arranged that when the control member is held and pulled by the rider, the catch holds the towrope, but on release of the control member, the release mechanism causes the catch to release the rope.

' SURF BOARDS This invention relates to surfboards of the kind which isintended to be towed behind a high-speed motorboat and which 7 Ihassufficient buoyancy to support a rider.

In my British specification No. 1.093.970 a sun beam of Forthis purpose,the surf board described in my prior specification had a seat which waspivotally mounted so that it could turn about an upright axis. a supponfor the feet of a rider to withstand the thrust of a towrope held by therider and a oddsusnnssts iq tbsssat s a m id= .ss ..wh !e e wasprovidedfor the towrope at the bow of the surf board so that as the towing boatturned and the towrope extended at an angle from the surf board, thepull still passed through the centerline of the board at its bow andassisted in turning the board to keep it in line with the towrope.

It was found, however, that this arrangement was not entirelysatisfactory because the pull from the towrope passing to the hands ofthe rider at a distance above the surf board applied. a turning momentto the surf board which tended to cause it to bury its bows. Because therider sat on a seat which was fixed in a fore and aft position he wasunable to alter the position of his own center of gravity in a fore andaft direction, as a done by a water skier, sufficiently to correct thetrim of the surf board and raise its bow to cause it to assume asau'sfactory planing position.

in order to overcome this difficulty, according to this invention. asurf board which has sufficient buoyancy to support a rider, a seatwhich is pivotally mounted so that it can turn holding a tow rope, steel; the surfboard by twisting the seat. A

v and rearwardly from the bracket. With the hook held in this The catchis preferably in the form of a hook' which is pivotally mounted on abracket fixed to the underside of the bow of the surf board. The hookhas a shank which projects from its pivot so that the hook and the shanktogether form a bell crank lever. The control member in the form of arope is connected to the free end of the shank and when this is pulledthe hook is held in a position in which it projects downwardly positiona loop on the end of a towrope will be held in he book when thetowropeextends under tension in a forward and slightly upward direction.To hold the loop of the towrope in the hook if the towrope should becomeslack, a spring extends from the shank adjacent the pivot to the freeend of the hook. The spring is pulled back to allow the loop of thetowrope to be held between it and the hook. If the rider of the boardreleases the control rope, the hook and its shank are turned about thepivot by the pull of the towrope so that the hook itself rocks forwardsuntil its free end points in the direction in which the towrope ispulled. When this happens the loop of the towrope immediately pulls overthe free end of the hook pushing the spring back from the free end ofthe hook so that the towrope is released.

when the rider is required to exert a pull on the control rope or othercontrol member equal or proportional to the pull in the towrope. thesurf board is provided with a support for the feet of the rider similarto that provided on the surf board described in my prior specification.This support withstands the thrust caused by the pull of the controlmember on the rider. The support is preferably made adjustable in a foreand aft direction to enable riders with widely different leg lengths tobe accommodated comfortably.

about an upright axis and a rudder which is connected to the seat sothat the rider can steer the surf board by twisting the seat,as in thesurf board described in my prior specification, is provided. at theunderside of its bow, with a catch for the attachment of a towrope, thecatch having a release mechanism controlled by a member which extendstowards the seat to enable it to be held by the rider, the mechanismbeing arranged so that when the member is held and pulled by the riderthe catch holds the towrope, but on release of the member, the releasemechanism causes the catch to release the rope.

With this arrangement, the pull from the towrope is applied to theunderside of the bow at approximately sea level and thus the towropetends to provide a slight upward pull towards its point of attachment tothe towing boat and this lifts the bow of the surf board so that itassumes the correct trim to plane over the surface of the water and anytendency for the surf board to bury its bows is completely overcome.

Even though the towrope is held by the catch, the fact that the riderhas to maintain a pull on the control member provides the rider with asensation similar to that of holding the towrope directly and if therider falls off the surf board or for any other reason releases thecontrol member, the towrope is at once released so that the surf boardremains with the rider as is the case when a directly held towrope isdropped in an emergency.

Preferably the catch and its release mechanism are con- An example of asurf board in accordance with the invention is illustrated in theaccompanying drawings in which:

FIG. I is a side elevation;

FIG. 2 is a plan;

HO. 3 is an underneath plan;

FIG. 4 is a section on the line lV-W in H6. 3; and.

HO. 5 is asection on the line V--V in FIG. 3.

The surf board has a hull 1 which is a hollow moulding-of glass fiberreinforced plastics material. The hollow moulding is made in the usualway in which small boat hulls are made by forming the complete mouldingin two sections and substrucfed tfiifch'aWaythat'either the 'pull of thetowrope is Iimsrnitted directly to the control member so that the rideris'proportional to that in the towrope. In the latter case the ridermust pull the control member with a force which is smaller han that inthe towrope but nevertheless varies with the pull of the towrope. Ineither case the effect is that the rider is given the impression that heis being towed by the contml member which adds to the enjoyment. Thecontrol member may be in the form of a handle connected by bars or otherrigid members to the catch release mechanism, out it is preferably inthe form of a rope of which the rider either holds a loop or which isprovided with a crossbar similar to the bars usually provided on theends of towropes for water skiing.

sequently sticking these together with an adhesive of the same plasticsmaterial as that out of which the mouldings are made. As shown mostclearly in FIGS. 4 and 5. the hull is divided into three compartmentsand is stiffened by two internal webs 2. It is also provided with acentral fin keel 3 and two-bilge fin keels 4.

The keels 4 are of hollow section as shown in FIGS. 4 and 5 and formrudimentary floats to give the hull a somewhat catamaranlike form as isnow common with small high-speed motorboats.

To maintain its buoyancy if the hull is damaged, it is filled with rigidpolyurethane foam 5 formed insitu. The central keel 3 is shorter thanthebilge keels 4 and extending from its after end is a strip of flexibleplastics material which forms a rudder 6. The forward end 7 of therudder 6-is moulded into the afterend of the keel 3 as shown mostclearly in FIG. 5. The rudder 6 projects beyond the afterend of the hulll. but its overall depth is very slightly less than that of the keels 4so that when the surf board is beached, the hull is carried by the finkeels 4 and the rudder 6 is p tected.

On the deck of the hull l is a further glass fiber reinforced mouldingforming a foot support 8 which is fixed to the hull l by bolts 9 passingthrough slots 10 so that on loosening the bolts the foot support 8 canbe adjusted in position in a fore and aft direction. Thesupport 8 isshown in FIGS. 1. and 2 in its most forward position.

Near its after end, the hull l is formed with a tubular socket 11 whichforms a pintle beas'l d into which a spigot 12 .The seat 13 is itself ahollow glass fiber reinforced plastics moulding which filled with rigidpolyurethane foam so that in itself it has substantial buoyancy.

turn. the rudder 6 is bent about its fixed forward end 7 and is itselfin effect turned to steer the surf board.

To enable the surf board to be towed by a motorboat. itis provided atthe underside of its bow with a catch and release mechanism :16. Thecatch-comprises a hook l'lwhichtogether with a shank l8 fixed to it forma bell crank lever which is pivotally mounted on a bracket 19 fixed tothe hull l. The afterend of the shank 18 is formed with an eye 19' andfixed in this eye is a rope 20 which forms a control member and extendsthrough a tube 21 moulded in the hull upwards in front of the footsupport 8 to a handle 22 at its upper end. When the handle 22 is graspedby a rider sitting in the seat 13 and is pulled, the book 17 is held inthe position shown in full lines in FIG. i of the drawings.

With the book 17 in this position, it will hold a loop formed on the endota towrope 23 and further, to hold the loop of the towrope23 in thehook 17 of the towrope becomes slack, a spring arm 24 is provided. Thespring arm 24 has one end rigidly fixed to the shank l8 and its otherend extends just beyond the hook 17. To allow the loop of the rope 23 tobe inserted in the hook 17, the spring arm 24 can be pulled back, thatis in an aft direction, until it is clear of the tip of the hook 17.

in use. the handle 22 is pulled as already described to hold the hook 17in the position shown in full lines in FIG. I and the surfboard is towedby the rope 23. To steer the surf board, the rider bends his knees andtwists to rotate the seat 13 and hence to turn the rudder 6. lf the surfboard is capsized or the rider is thrown off, he releases the handle 22and this allows the bell crank lever formed by the hook 17 and the shank18 to turn under the pull of the towrope 23 into the position shown inchain-dotted lines in HG. was! the hook 1'! in this position, the pullof the towrope pulls its loop away from the hook l7 against the spring24 which flexes and at once allows the loop of the towrope 23 to bepulled away and completely released.

If owing to some unforseen circumstances the towrope 23 Y becomessnarled and fails to be released from the hook 17, the spigot 12 willpull out of the socket it if the surf board capsizes so that the seat13, which is buoyant is released and ac& as a float for the rider. ifnecessary, the rider can be strapped or otherwise held in the seat 13 sothat if he falls off the surf board and the surf board is towed a shortdistance before the towrope is released, the seat will automaticallybecome detached and at all times remain with the rider.

The angle at which the towrope 23 extends to the horizontal is slightlyexaggerated in FIG. 1 of the drawings. but owing to the position of thehook 17 on the underside of the bow of the surf board, the towrope willtend to lift the bow and ensure that the surf board planessatisfactorily.

1 claim:

I. A surf board comprising a hull including a bow portion, said hullhaving sufficient buoyancy to support a rider, a seat for said rider,means pivotally mounting said seat on said hull for turning movementabout an upright axis, a rudder, means attaching said rudder to saidhull for turning movement relative thereto. mcnns operatively connectingsaid sent in mid rudder whereby said rider cun steer iutid surf board byturning 1 said seat, a catch for the attachment of u towrope and meansattaching said catch to the underside of said bow portion of said hullfor movement independently of said steering means between a towropeholding position and a release position. and release means including amember which extends from said catch towards said seat to enable it tobe tensioned by said rider, said catch being mounted to be moved to itsrelease position when there is tension on a towrope engaged by saidcatch unless restrained from'such movement by countervailin tension onsaid release means. 0

. A surf boardas claimed in claim 1, wherein said release means includesmeans for transmitting tension in said towrope directly to said member.-

3. A surf board as claimed in claim 2, wherein said member includes arope and a handle fixed to said rope, said handle being arranged to beheld by said rider.

4. A surf board as claimed in claim 2, wherein said catch comprises ahook for receiving a'loop on said towrope, said catch-attaching meansincludes a bracket attached to the underside of said bow portion of saidhull, means pivotally mounting said hook on said bracket, a shankprojecting from said hook, said hook and said shank together forming abell crank lever and said shank having a free end remote from said hookand said member being attached to said free end of said shank wherebywhen said member is pulled by said rider, said hook is held in aposition in which it projects downwardly and rearwardly from saidbracket to hold said towrope, but when said member is released said hookswings forwards under the pull of said towrope to release said towrope.

5. A surf board as claimed in claim 4, further comprising spring meansextending from said shank adjacent said pivot to the free end of saidhook, said spring means being arranged to hold said towrope in said bookwhen said towrope is slack.

6. A surf board as claimed in claim 1, further comprising foot supportmeans on said hull for withstanding thrust'applied to said rider bytension in said control member.

7. A surf board as claimed in claim 6, further comprising means movablymounting said foot support means on said hull I for adjustment inposition in a fore and aft direction.

8. A surf board as claimed in claim 1, wherein said rudder includes astrip of flexible material and means fixing said strip of flexiblematerial to said hull at the forward end of said strip.

9. A surf board as claimed in claim 8, wherein said means operativelyconnecting said seat to said rudder comprises an arm fixed to andextending aft from said seat and means projecting downwards from the aftend of said arm behind said hull and straddling the after end of saidrudder.

10. A surf board as claimed in claim 1, wherein said means mounting saidseat on said hull includes means defining a socket in said hull and aspigot on said seat, said spigot fitting removably in said socket.

ll. A surf board as claimed in claim 10, wherein said seat includesbuoyancy means assisting flotation of said rider when said seat isdetached from said hull.

12. A surf board as claimed in claim I, further comprising two-fin bilgekeels fixed to said hull.

13. A surf board as claimed in claim 12, wherein said bilge keelsproject downwards beyond said rudder whereby said keels protect saidrudder when said surf board is beached.

' U i I i

1. A surf board comprising a hull including a bow portion, said hullhaving sufficient buoyancy to support a rider, a seat for said rider,means pivotally mounting said seat on said hull for turning movementabout an upright axis, a rudder, means attaching said rudder to saidhull for turning movement relative thereto, means operatively connectingsaid seat to said rudder whereby said rider can steer said surf board byturning said seat, a catch for the attachment of a towrope and meansattaching said catch to the underside of said bow portion of said hullfor movement independently of said steering means between a towropeholding position and a release position, and release means including amember which extends from said catch towards said seat to enable it tobe tensioned by said rider, said catch being mounted to be moved to itsrelease position when there is tension on a towrope engaged by saidcatch unless restrained from such movement by countervailing tension onsaid release means.
 2. A surf board as claimed in claim 1, wherein saidrelease means includes means for transmitting tension in said towropedirectly to said member.
 3. A surf board as claimed in claim 2, whereinsaid member includes a rope and a handle fixed to said rope, said handlebeing arranged to be held by said rider.
 4. A surf board as claimed inclaim 2, wherein said catch comprises a hook for receiving a loop onsaid towrope, said catch-attaching means includes a bracket attached tothe underside of said bow portion of said hull, means pivotally mountingsaid hook on said bracket, a shank projecting from said hook, said hookand said shank together forming a bell crank lever and said shank havinga free end remote from said hook and said member being attached to saidfree end of said shank whereby when said member is pulled by said rider,said hook is held in a position in which it projects downwardly andrearwardly from said bracket to hold said towrope, but when said memberis released said hook swings forwards under the pull of said towrope torelease said towrope.
 5. A surf board as claimed in claim 4, furthercomprising spring means extending from said shank adjacent said pivot tothe free end of said hook, said spring means being arranged to hold saidtowrope in said hook when said towrope is slack.
 6. A surf board asclaimed in claim 1, further comprising foot support means on said hullfor withstanding thrust applied to said rider by tension in said controlmember.
 7. A surf board as claimed in claim 6, further comprising meansmovably mounting said foot support means on said hull for adjustment inposiTion in a fore and aft direction.
 8. A surf board as claimed inclaim 1, wherein said rudder includes a strip of flexible material andmeans fixing said strip of flexible material to said hull at the forwardend of said strip.
 9. A surf board as claimed in claim 8, wherein saidmeans operatively connecting said seat to said rudder comprises an armfixed to and extending aft from said seat and means projecting downwardsfrom the aft end of said arm behind said hull and straddling the afterend of said rudder.
 10. A surf board as claimed in claim 1, wherein saidmeans mounting said seat on said hull includes means defining a socketin said hull and a spigot on said seat, said spigot fitting removably insaid socket.
 11. A surf board as claimed in claim 10, wherein said seatincludes buoyancy means assisting flotation of said rider when said seatis detached from said hull.
 12. A surf board as claimed in claim 1,further comprising two-fin bilge keels fixed to said hull.
 13. A surfboard as claimed in claim 12, wherein said bilge keels project downwardsbeyond said rudder whereby said keels protect said rudder when said surfboard is beached.